Manufacture of stable dry papain composition



Patented Mar. 15, 1949 MANUFACTURE OF STABLE DRY PAPAIN COMPOSITION Lloyd A. Hall, Chicago, Ill., assignor to The Gritfith Laboratories, Inc.,

tion of Illinois Chicago, 111., a corpora- No Drawing. Application February 24, 1945,

Serial No. 579,682

' 4 Claims.-

This present invention relates to meat-tenderizing compositions, and in particular to one in a dry pulverulent form containing sodium chloride as the principal vehicular component for the proteolytic enzyme papain.

Papain is a well known and commercially used agent for tenderizing meat. It is commonly dispensed in liquid for-m in salt solution for use in restaurants, institutions, and even in the home. Attempts to provide papain in dry composition have not been successful because of a loss of activity by deterioration. The present invention is directed to overcoming this deterioration in a stable dry composition.

It is an object of the invention to provide a dry granular stable papain composition for tenderizing meat.

It is a particular object to provide a dry papain composition containing a large quantity of sodium chloride, which is not subject to loss of activity of the papain.

It is a particular object of the invention to bufier a dry composition of sodium chloride and papain to a pH in the range from 5.5 to 7.

Various other and ancillary objects and advantages of the invention will appear hereinafter.

In studying the loss of activity of papain in dry compositions, these were made with a diluent or vehicular base because the amount of papain necessarily dispensed for actual use is very small. Sodium chloride was used as a base, because it has been heretofore observed in the literature that papain in such salt solution retains its activity, but on drying'such solution, the activity is lessened or lost. See article entitled Drying of papaya latex-stability of papain, by A. K.

Dept, of Agriculture, in Industrial and Engineering Chemistry, vol. 32, p. 1277, Sept. 1940. Ap-

plicant has also found that freshly dried papaincontaining salt solutions lose activity only gradually on aging. This indicated a change to be taking place. Knowing that dry papain is stable and that dry salt is stable, it was suspected that some combination effect is responsible for the loss of activity.

Papain has a pH of about 5.5 and it is known to be stable in compositions of high pH up to 7. Meats to be tenderized have a pH within this range from 5.5 to 7, and usually not over pH of 6.5, and commonly lower.

I have discovered that having present a buffering agent in a dry composition of sodium chloride and papain to maintain the composition in the range of pH from 5.5 to 7, and preferably from Balls, H. Lineweaver, S. Schwimmer, of U. S.

5.5 to 6.5, the papain does not lose its activity upon aging the composition. It is believed that some unknown reaction effects a generation of trace quantities of hydrochloric acid from the sodium chloride, resulting in damage to the papain. The action is believed to be akin to the bleaching of oleoresin of capsicum in a dry vehicle of sodium chloride, which can be remedied by pH control, as set forth in the Grifiith and Hall U. S, Patents, No. 1,995,119 through No. 1,995,121, and No. 2,032,612.

According to the present invention then, dry solid sodium-chloride base compositions containing papain are buffered to a pH in the range from 5.5 to 7, and preferably in the range from 5.5 to 6.5. Reference to pH values of the composition of the present invention signifies that the same has been determined on a solution consisting by weight of 1 part of the composition and 9 parts of water, using a glass electrode.

The composition of the present invention may be made as a free-flowing one, so that it may be used in a household to sprinkle on both sides of a piece of meat, as from a shaker, and allowed to stand for about 15 to 20' minutes before cooking.

A very small amount of papain is effective, making it necessary to use small amounts of papain. Hence, a relatively large amount of diluent is used, which is such as to provide the vehicular base of the composition. Since sodium chloride is normally. added to season meat, sodium chloride is used. Small quantities of sugar may be present, but this is undesirable because the taste of sugar is not generally acceptable with meat, except with ham. Furthermore, sugar is undesirable in the composition of the present invention because of hygroscopicity, leading to caking of the composit on. This is especially true of corn sugar, and of large amounts of any sugar. However, where the dry composition consists of at least sodium chloride, and is adequately buffered, other ingredients may be present, including commercial corn sugar, which contains traces of hydrolyzing acid. The amount of sugar which can thus be present is not suffioient to be distasteful, or to cake the composition, or to exhaust the buffering agent when corn sugar acidity is present.

Other ingredients may be added as desired, Spices and the like may .be present, but, in general, these are omitted. However, for the purpose of psychological effect by aroma and as well for taste, the composition is givena meat-like aroma and flavor by including meat-like flavors,

' 3 such as one or more of the amino acid salts, or a beef extract. A suitable flavor is the residue of a vegetable or animal protein hydrochloric-acidhydrolysate from which the glutamic acid component has been removed, as is frequently done to manufactm'e mono-sodium glutamate. Wherein such residue is used as a meat-like flavor, it is usually neutralized by sodium hydroxide or a carbonate to a pH in the range from bullering agent is applied to the meat and consumed with it,'a wide range is available.

The product may be a physical mixture of the ingredients, but it is preferred to homogenize all the ingredients other than the vehicular sodium chloride crystals, or at least to homogenize that part of it including the papain and the bufiering agent.

The temperature to which the product is subjected in drying afiects'theactivity, the higher a non-killing temperature, the less the activity. Temperatures up to 140 F. may be used, and at this temperature there is some destruction, but also a useful remnant of activity. Above 140 F., the results are unsatisfactory. There is no precise relation between temperature and residual activity, because time is also a factor. Thus small batches more quickly dried at a given temperature are more active than larger batches of the same composition similarly dried but in longer time. In a vacuum pan drier, it takes about 2 hours to dry a 1500 lbs. batch as given below in Example 1, at a temperature not over 120 F.,

and high activity is obtained. Time may be shortened by use of higher temperatures, but such large batches should not be subjected in drying to temperatures over 140 F., for satisfactory results, but preferably not over 120 F. for the best results.

The following examples illustrate the invention.

Example 1 Papain Y 6'! lbs. 8 ozs. Corn starch 60 lbs. Normal sodium citrate 30 lbs. Beef extract 11 1bs.4 ozs.

Flake salt 1331 lbs. 4 025. Water, 11 gallons Total 1500 lbs. solids The composition is preferably made by 1) dissolving lbs, of the salt in 5 gals. of the water, and add the papain; (2) dissolve the beef extract in 2 gals. of the water; (3) dissolve the sodium citrate in 4 gals. of the water; (4) mix three solutions; (5) mix the remainderof the salt and the starch in a mixer; (6) mix the liquid into the solid to uniformity; (7) deliver to a vacuum evaporating crystallizen-and dry out the water to a granular product at a temperature not over 160 F. The pH in a 10% solution is 6.4.

The drying is efiected at a pressure of 29 inches of mercury, and water is first given off at 77 F.

as the material dries in the course of about 2 hours, the vacuum goes up to approach 29% inches of mercury, and the temperature goes up to approach 115 F. In general, when the water in the receiver drips very slowly, the drying is considered complete, and this may be at a final temperature in the range from 110 to 115 F. in two hours, for the quantity of Example 1 in the particular equipment used.

In the foregoing, the salt is 89% of the composition, the papain about 4.5%, and the buttering agent about 2%. The corn starch is binder for providing a thin skin as a film covering on.

salt crystals, and it houses the papain, sodium citrate and beef extract flavor.

Example 2 In Example l the 30 lbs. of sodimn citrate is changed to lbs. of triethanolamine, and the salt is increased by 15 lbs.

Papain 13.5

, Animal protein hydrolysate (glutamic-acid free) 33% solids, pH of 7 32 Corn start-h 15 Calcium carbonate 5 Sodium chloride 300 The composition is made substantially as in Example 1, The pH is about 7. The salt is about 88% of the composition.

Example 4 Papain 4.5 lbs.

Potato starch 5 lbs.

Beef extract .75 lb.

Triethanolamine 3.5 ozs.

Sodium chloride 90 lbs., 125 ozs.

Water 1 5.5 pints The composition is made substantially as in Example 1. The pH is 6.8. The salt is about 90% of the composition.

Example 5 Mixture A is made first:

Flake sal lbs '16 7 Corn starch "025.. 5.5

Papain ozs 1.75 Normal sodium citrate ozs- 8 Neutralized vegetable protein hydrolysate (67% water, 4% sodium chloride) at pH of 5.2- lbs 10.5 Sodium bicarbonate --ozs..- I

The above are compounded substantially as in Example 1, to a dry powder of coated salt crystals. It is about 95% sodium chloride.

The following is then physically compounded:

Curing salt containing heart-like centers of sodium nitrate and sodium nitrite (about NaCl) lbs Brown sugar lbs 2.5 Clarified sugar lbs- 7.5 Sodium bicarbonate o2s 5.75 Mixture A lbs 76 In the above, the sodium bicarbonate may be 1. The method which comprises wetting sodium chloride crystals with a film-forming aqueous composition containing papain and a buflering agent, and drying the mass at a temperature not over 140 F. and forming a thin skin as 9. him coat on the resulting salt crystals, the'buflering agent maintaining the composition at a pH in the range from 5.5 to 7 measured as a 10% by weight solution in water.

2. The method of preserving the activity of papain in the presence of sodium chloride which comprises drying at a temperature not over 140 F. and within a period of two hours, an aqueous mass containing sodium chloride and papain in the presence of a buflering agent in quantity maintaining the dried residue at a pH in the range from 5.5 to 7 measured as a 10% by weight solution in water. i

3. The method of preserving the activity of papain in the presence of sodium chloride which comprises drying at a temperature not over 120 F. and within a period of two hours an aqueous mass containing sodium chloride and papain in the presence of a builering agent in quantity maintaining the dried residue at a pH in the range from 5.5 to 7 measured as a 10% by weight solution in water.

4. The method of preserving the activity oi papain in the presence of sodium chloride which comprises drying at a temperature not over 120 F. in about two hours, an aqueous mass containing sodium chloride and papain in the presence of a buffering agent in quantity maintaining the dried residue at a pH in the range from 5.5

to 7 measured as a 10% by weight solution in water.

LLOYD A. HALL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name I Date 2,140,781 Allen Dec. 20, 1938 2,313,875 Jansen Mar. 16, 1943 OTHER REFERENCES 

